Device for dewaxing carton conveyors



March 14, 1961 Filed June 2, 1958 H. G. THOMPSON DEVICE FOR DEWAXING CARTON CONVEYORS 2 Sheets-Sheet 1 COOLER CARTON ERECTOR a WAXER DE-WAXER CARTON CARTON REMOVAL FILLER INVENTOR. Harr y 6. Thompson A TTORNEYS March 14, 1961 H. G. THOMPSON 2,974,631

DEVICE FOR DEWAXING CARTON CONVEYORS Filed June 2, 1958 2 Sheets-Sheet 2 will! [0a [3 [4 i" Ii M h va -w Fig.2

INVENTOR. Harry 6. Thompson BYEIQFJWMM United States Patent 2,974,631 DEVICE FOR DEWAXING CARTON coNvEYoRs Harry G. Thompson, 2011 s. Ionia, Grand Rapids, Mich. Filed June 2, 1958, Ser. No. 739,369 4 Claims. 01. 118-40 This invention relates to a device for dewaxing carton conveyors. More particularly, this invention relates to a device which simultaneously applies a liquid parting agent for wax type materials to a conveyor and brushes the set wax substances from it. v

In the use of waxed food cartons, equipment is provided to erect and wax the carton. The carton is then deposited on a conveyor for movement to another station while the wax cools and. hardens. At one point on these conveyors, the cartons are automatically erected and coated with hot, liquid wax. The cartons then move along the conveyor to be automatically cooled, in order to set the wax, and removed by a jet stream of air to other suitable equipment for filling and closing them. A great many products are now packaged in waxed containers including milk, frozen fruits and vegetables, etc.

Expediency and efficiency have become necessities to this packaging process. However, one major problem slows down this process and lowers the eflficiency of the operation. When the cartons are erected and waxed, and begin their journey along the'conveyor, the wax is still hot and flowable. Some of this hot wax runs onto the conveyor. Some of it is scraped oil? the cartons as they are deposited on the conveyor. These conveyors are usually characterized by a plurality of articulated fiat links. The hot wax deposited on these links is cooled in the next step of operation, and thus is hardened and adheres firmly to the links. The repeated deposit of wax on the conveyor as it passes through numerous cycles of operation causes a substantial quantity of wax to accumulate. It does not take long for suificient wax to be deposited on the links of the conveyor elements to cause mal-functioning of the system. Prior to this invention, the wax deposits had to be removed manually. This was slow and laborious. It seriously reduced the operating efficiency of the machine by necessitating lengthy periods of inoperativeness. The hardened wax rapidly built up thick layers firmly adhering to the links of the conveyor.

When the unfilled, opened cartons are removed from the conveyor by a jet of air, portions of the wax deposit were frequently dislodged from the conveyor by the air blast and blown into the erected but still open carton. Since it is quite displeasing to the ultimate consumer of the goods to find small bits of hard wax mixed with the contents of the carton, many attempts have been made to prevent the wax from entering the carton. However,

the industry prior to this invention had never successfully overcome this problem.

Where efficiency is so important to an art, in this case both from the standpoint of competition and the elimination of contaminants from the product being packaged, the development of an inexpensive and effective solution is essential. It is therefore an object of this invention to provide a means for continuously and automatically removing these wa'x deposits from the links of the conveyor element.

Another object of this invention is to provide such a Patented Mar. 14, 1961 ice means which is simple in operation and inexpensive to construct.

Another object of this invention is to provide such a device characterized by functional efficiency and dependability.

Another object of this invention is to provide a means for keeping wax from accumulating on the links of the conveyor and thereby keeping to a minimum the amount of wax entering the carton during its removal from the conveyor.

Another object of this invention is 'to provide such a device which also reduces wear of the conveyor structure.

Other objects of this invention will become obvious to those skilled in the art of packaging upon reading the v accompanying specification and examination of the accompanying drawings, in which:

Fig. 1 is a flow diagram of a conventional packaging process, showing this invention in combination therewith.

Fig. 2 is a fragmentary oblique view of a section of one type of conveyor element.

Fig. 3 is a side elevational view of this invention in combination with the conveyor element shown in Fig. 2 with one of the side standards ofthe dewaxer removed.

Fig. 4 is a cross sectional plan view taken along the plane IVIV :of Fig. 3.

Fig. 5 is a sectional elevational view plane V-V of Fig. 4.

Fig. 6 shows a fragmentary, partially broken, oblique View of the brush element of this invention and of the conduit means upon which it is mounted.

Briefly, this invention comprises a device for eliminating wax from a conveyor having a driven conveyor ele ment and generally characterized by a plurality of articulated flat links arranged in two spaced parallel planes. The device includes an applicator supported in contact with a fiat surface of the conveyor, a source of liquid parting agent for wax type materials, and a means for discharging metered quantities .of this parting agent on the flat surface of the conveyor, the applicator brushing the parting agent .on the flat surface and simultaneously brushing the wax from it. The device is constructed so as to adapt the device to operate directly from the moving conveyor itself, thus eliminating the necessity for a separate power source.

This invention also involves a method for dewaxing carton conveyors, the steps in this method including the simultaneous brushing and applying of a liquid parting taken along the loading station whereheated waxed substances become deposited on it, and allowing the waxed substances to set. After the wax has set, the Wax is brushed from the conveyor and a new film of liquid parting agent is applied thereto. Y

Referring now to the drawings, Fig. 1 shows the major steps in a packing operation. The reference numeral 1 designates an endless, continuous conveyor traveling through a carton erector and waxer station, a carton cooler station to harden the wax, a carton removal station and a conveyor dewaxing station. At the carton removal station the cartons are ejected from the conveyor by an air jet and directed to suitable carton filling and closing equipment. This invention is concerned with the dewaxing station, the other stations being conventional and of no particularimportance to this invention except to provide the environment of the inventions operation.

Fig. 2 shows a section of the conveyor element. In order to, clarify and precisely. describe the parts of this invention and the independent and combined features thereof, a conveyor element adapted to move waxed milk cartons has been shown in the drawings. It should be understood that'this invention can be adaptedfor use with any conventional conveyor for waxed cartons. A conveyor characterized by a plurality of articulated links is shown in the drawings. The conveyor element 1 is driven in an endless fashion by a conventional prime mover (not shown). The conveyor includes the supporting rails 2 and the side rails 3 on each side thereof. The side rails 3 have an upstanding flange for confining the lateral movement of the moving conveyor element. The movable element 4 rides along on the rails 2 and is guided by the flanges of the side rails 3. The movable element 4 is comprised of a series of articulated links 5, each link including an upper portion 6 and a lower portion 7. These links are pivotally connected by pins 8 joining the upper portion 6 of the links end to end and also the lower portions of these links end to end. The spacers 9 envelop pins 3 and properly space the upper and lower portion of the links. Such a movable element is adapted to receive tall cartons such as waxed milk cartons C and move them along. Having described the conveyor shown in the drawings, a description of this invention used in combination therewith follows. However, this invention is adapted to operate effectively in combination with any type of conveyor elements upon which wax accumulates during use.

Figs. 3, 4 and 5 best show this combination. The reference numerals 10 and 10a designate supply tanks or sources of liquid parting agent for waxed type materials. The conduit means 11 and 11a transmit this liquid parting agent from the sources 10 and 10a respectively to the brush elements 20, 30 and 40 which apply it to the movable element 4 of the conveyor 1 as they scrape against it. In the drawings, the brush elements 20, 30 and 40 are shown to be rotatably mounted on the conduit means 11 and 11a. However, this dewaxer also works extremely well if these brushes are stationary, the conduit means 11 and 11a supplying them with parting agent, and the brushes simultaneously applying the parting agent to the conveyor and scraping the wax from it. However, the following description will only concern rotary brushes, as this is deemed sufficient for an understanding of this invention, whether rotary or stationary brushes are utilized.

The brush element 20 is rotatably mounted on conduit means 11 so that it brushes against and applies the parting agent to the upper portion 6 of the links 5 of the conveyor. The brush elements 30 and 40 are rotatably mounted on the conduit means 11a so that they brush against and apply the parting agent to the lower portion 7 of the links 5 of the conveyor. This entire structure is mounted on and supported by the plates 17 and 18, each of which is mounted on a side rail 3.

The plates 17 and 18 are mounted on the side rails 3 of the conveyor 1 by the bolt assemblies 15'. The conduit means 11 and the conduit means 1111 are mounted on the plates 17 and 18 and consist of conventional links of tubing. Conduit means 11 is suitably mounted through openings near the tops of side plates 17 and 18 so that it lies above the upper portions 6 of articulated links 5 (Fig. 4). Conduit means 11a is suitably mounted through openings near the bottom of side plates 17 and 18 so that it lies above the lower portion 7 of the articulated links 5. The structure of source 10, conduit means 11 and brush elements 20 will now be described in detail, these elements keeping the top portion 6 of links 5 free of wax. A general description of source 10a, conduit means 11a and brush elements 30 and 40 will follow, these elements keepingthe lower portion 7 of links 5 free of wax, it being deemed that this will be suflicient for an understanding of this invention since these systems operate in the same manner and on the same principles.

Conduit means 11 includes the tube 12 lying above the upper portion 6 of the links 5. This tube 12 extends through the plates 17 and 18 and conduit means 11 extends upwardly and communicates with the source 10, supporting it above the conveyor. The check valve 13 4 is mounted in conduit means 11 just below source 10, the check valve only allowing one way passage of liquid. Check valve 13 is positioned to lie at an angle of approximately degrees to the plane of the conveyor. It has been found that an angle of 90 degrees allows too much of the parting agent to escape through the check valve, and an angle substantially less than 45 degrees does not allow enough parting agent to come through the check valve. The portion of tube 12 lying between the plates 17 and 18 has small apertures 15 along its top, the purpose of which will be explained hereinafter.

The source 10 may be any type of container suitable for holding the parting agent. Any suitable parting agent for wax type material may be placed in source 10. Experiments have shown that a mixture of glycerine and mineral oil comprises an efiective parting agent. For example, a mixture consisting of approximately one part glycerine to six parts mineral oil has been found to be eifective. It will be readily noted that this parting agent will flow from the source 10 through the check valve 13. A source of compressed air 14 is connected to conduit means 11 at a point between the check valve 13 and the portion of the tube 12 lying between the plates 17 and 18. It has already been noted that the cartons are removed from the conveyor by compressed air applied in intermittent surges as each carton reaches the proper position on the moving conveyor. This same compressed air may be utilized to facilitate the entry of the parting agent into the portion of tube 12 of conduit means 11 lying between the plates 17 and 18. Because the intermittent surges compressed air depend on the conveyor moving a predetermined distance, that is, a surge of air as each carton reaches a certain point on the conveyor, an even spread of parting agent is assured as it is applied in a manner dependent on the conveyors movement.

. Thus, as a metered quantity of the parting agent escapes through check valve 13, its placement being at an angle of approximately 45 degrees helping to assure that a proper amount escapes from source 10, intermittent surges of compressed air force this metered quantity of parting agent into the portion of tube 12 of conduit means 11 lying between the plates 17 and 18. The ultimate flow from the check valve and the surge of compressed air assures that the proper amount of parting agent enters this portion of the tube 12.

Fig. 5 shows a cross section of the brush element 20 of Fig. 3. This brush element includes a hollow core 21 and the bristles 22 extending radially outwardly from the core 21. These bristles may be fabricated of any material which is inert to the parting agent to be used and is of suflicient strength to properly scrape against the upper portion 6 of the links 5. The hollow core 21 of brush element 20 is adapted to receive that pontion of the tube 12 of conduit means 11 lying between the plates 17 and 18. Core 21 is of such a size that a chamber 25 is formed between it and tube 12 of conduit means 11. Brush element 20 is rotatably mounted on this section of the tube 12 spaced directly above the upper portion 6 of the links 5 of the movable element 4 of conveyor 1, by the bushings 23. These bushings also space core 21 from tube 12 to form the chamber 25. The bristles 22 are of such a length that they constantly engage the upper portion 6 of links 5.

Fig. 6 shows a detailed view of a section of the core 21 rotatably mounted on the tube 12 of conduit means 11. The core 21 has a series of openings 24 along its length. The tube 12 has a series of small apertures 15 corresponding to the openings 24 in the core 21 of brush element 20. The openings 15 in tube 12 are positioned along the top thereof, thereby assuring that the parting agent will flow in uniform quantity from tube 12 into chamber 25 throughout the length of the tube. This is because the tube 12 will be filled with the parting agent before the parting agent escapes from it. When a surge of compressed air forces more parting agent into tube 12, the parting agent is forced out evenly throughout the length of the tube into chamber 25. Thus, an even, metered amount of parting agentis assured throughout the width of the links of the conveyor, as well as the length of the conveyor as noted hereinbefore. The purpose and function of this structure is now readily seen from an examination of Figs. 2, 3, 4, 5 and 6. As the moving element 4 of conveyor 1 moves along the conveyor, the upper portion -6 of the links '5 of movable element 4 engages the bristles 22 of the brush element 20, causing it to rotate. The parting agent flows from its source 10- through check valve 13, and with the aid of intermittent surges of compressed air continues through conduit means 11 and into the section of tube 12 lying between the plates 17 and 18. A metered quantity of this parting agent exits through the small apertures 15 of the tube 12, into the chamber 25, then through the corresponding openings 24 of the core 21 of brush element 20 and onto the bristles thereof. The bristles of the brush element 2 scrape against the upper portion 6 of all of the links 5 as they pass along the conveyor, simultaneously applying a film of the parting agent thereto. The wax deposits accumulated on the upper pontion 6 of the links 5 are scraped from these links once during each cycle of the movable element 4. At the same time, a new film of the parting agent is applied to prevent the wax from adhering to the surface thereof as the cycle is continued. Thus the wax deposits on each link 5 are removed therefrom once during each of the cycles of the conveyor 1.

Because of the spacers 9, which space the upper and lower portions of the links 5 of the movable element 4 from each other, two brush elements 30 and 40 (Figs. 3, 4 and 5) are required to remove the wax deposits from the bottom portions 7 of these links 5. However, the structure of the individual brush elements 30 and 40 (Fig. 5) is much the same as that of brush element20 described above. Conduit means 11a includes the tubes 12a and 12b which are mounted-to extend through the plates 17 and 18 respectively. These tubes, 12a and 12b are positioned to lie above the lower portion 7 of the links 5, terminating just short-of the path traced by the spacers 9 as they move along the conveyor. Conduit means 11a extends upwardly from the tubes 12a and 12b and the source 10a is connected thereto and mounted to lie above the conveyor. in conduit means 11a between the source 10a and the portions of the tubes 12a and 12b lying between the plates 17 and 18. Check valve 13a is also positioned at approximately a 45 degree angle relative to the conveyor for the reasons noted hereinbefore. The compressed air source is connected to conduit means 11 between the check valve 13a and the portion of the tubes 12a and 12b lying between the plates 17 and 18, by the hose 14a. The tubes 12a and 12b have small apertures 15a lying along the top thereof.

Brush elements 30 and 40 are rotatably mounted on the tubes 12a and 12b respectively (Fig. 5). These brush elements 30 and 40 have the cores 31 and 41 respectively and the bristles 32 and 42, respectively. These brushes are positioned on the tubes 12a and 12b by means of the bushings 33 and 43, the core 31 and 41 being of a size formingthe chambers 35 and 45. The cores of the brushes 30- and 40 have the small rows of openings 34 and 44, corresponding with the openings 15a in the tubes-12a and-12b noted above. It will now be noted that as the links 5 of the movable element 4 of the conveyor move along, the lower portion 7. of the links 5 will engage the bristles '32 and 42 of the brush elements 30 and 40causing these brush elements to rotate. The parting agent exits from the source 10a, a metered quantity passes through check valve 13a, and with the help of intermittent surges of compressed air applied to conduit means 11a, this metered quantity of the parting agent enters into the tubes 12a and 12b. The parting agent then enters the chambers 35 and 45, exits through the openings 24 and 34 onto the bristles of these brush Check valve 13a is mounted of them, and at the same time apply a film of parting agent to them. Thus, both the upper and lower portions of the links 5 continuously remain free of troublesome wax deposits. 1

Mounted on each side plate 17 and 18 is a brush 50 adapted to scrape against the spacers 9 and also the upper and lower portion of the links 5 of the conveyor. (Figs. 3 and 4.) These brushes are positioned behind brush elements 20, 30v and 40 relative to the direction of the movement of the conveyor and are half-circular in shape, since both ends of each brush are secured to a side plate. These brushes give added assurance that the wax will be scraped from the links of the conveyor.

Assembly and operation This invention is adapted to be mounted on any conventional waxed carton conveyor. The entire structure is adapted to be supported by two side plates mounted on the sides of the conveyor. This invention may be mounted and removed as a unit without interference with or modification of the conveyor itself.

Tube 12 is mounted through openings in side plates 17 and 18 so that it lies above the upper portions 6 of the links 5, tube 12 being a part of conduit means 11. Conduit means 11 then extends upwardly and supports the supply tank or source 10, communicating therewith. The check valve 13 is positioned at approximately a 45 degree angle between source 10 and tube 12. The source tween check valve 13 and tube 12 at 14. The brush element 20 is rotatably mounted on the tube 12 between the side plates 17 and 18, positioned to engage the upper portions 6 of the links 5.

Brush elements 30 and 40 are assembled and mounted on the conveyor in much the same manner, except that to allow the spacers 9 to pass through the dewaxer, a pair of tubes 12a and 12b are provided, each mounted in a side plate, and each terminating just short of the path traversed by the spacers 9. Conduit means 11a extends upwardly from the tubes 12a and 12b, and source 10a is supported above the conveyor thereby, communicating therewith. Again, a check Valve 13:: and a compressed air supply 14 are also mounted in conduit means 11a, the brushes 30 and 40 being rotatably mounted'on the tubes 12a and 12b.

Brushes 50 are mounted behind brush elements 20, 30 and 40 relative to the direction of the movement of the conveyor, the ends of one of. these half-circular shaped brushes mounted on each side plate so that it lies between the upper and lower portion of links 5 and allows the spacers 9 to pass therebetween (Figs. 3 and 4).

The operation of this device should be obvious from the above description. The bristles of the brush elements engage the upper and lower portions 6 and 7 of links 5 ofthe movable element 4 of the conveyor 1. As the movable element 4 moves along the path traced by the flanges 3 of the conveyor, the brush elements 20, 30 and 40 will rotate. The parting agent will drop from its sources 10 and 16a into conduit means 11 and 11a respectively, a metered quantity of this parting agent passing through the check valves 13 and 13a. The pressure exerted by the intermittent surges of compressed air entering conduit means 11 and 11a at 14 and 14a respectively, will convey the parting agent through the tubes v12, and 12a and 12b. This panting agent emerges evenly throughout the length of these tubes and enters the chambers 25', 35, and 45 formed by the cores of the brush elements and these tubes. This parting agent then exits through the openings 24, 34, and 44 in the cores of the brush elements 20, 30* and 40 respectively, onto the bristles 22, 3-2 and 42 of the rotating brush elements. These bristles are constantly scraping against the upper and lower portions 6 and 7 of the links 5 and simultaneously applying a film of the parting agent thereto. The wax deposits on the links are continuously scraped therefrom, and each link receives a new film of the parting agent which prevents the wax from ever adhering to the surfaces of the links. Each link receives such a coating and scraping once during each of its cycles in the endless conveyor system. The brushes 50 give added assurance that the loose wax on the link will be scraped away.

This invention eltectively removes the wax deposits which accumulate on a conveyor operating in the manner described. This device is simple in construction and can easily be assembled in combination with such conveyors. This simplicity of design makes the device both economical to produce and maintain, and certain in performance. The wax deposits are automatically and continuously removed. Large wax deposits are never allowed to accumulate. This dewaxers construction allows it to operate directly from the movement of the conveyor, thus requiring no independent power source.

Because the wax cannot accumulate on the conveyor, this invention solves the problem of small bits of wax finding their way into the carton to become mixed with the contents thereof. Also, the parting agent is quite effective in lubricating the parts of the conveyor itself, thereby greatly reducing wear and increasing the work life of the conveyor unit itself.

It should be understood that this invention can be practiced with different embodiments than those described herein. For example, one supply tank for both conduit means rather than two independent units could be devised. Also, as previously pointed out, the brushes need not rotate to apply the parting agent to the conveyor and scrape the wax therefrom, as this invention encompasses the concept of both rotary and stationary brushes mounted on the conduit means. Various other changes could be made without departing from the scope of this invention. These embodiments are to be included within the spirit and scope of this invention and unless the following claims expressly state otherwise.

I claim:

1. In an apparatus for applying wax to articles, which has a continuous conveyor characterized by a plurality of articulated flat links arranged in a pair of spaced parallel planes, said apparatus comprising article depositing means for depositing articles to be waxed on said conveyor, wax applying means for applying wax to said articles on said conveyor and waxed article removal means for removing waxed articles from said conveyor with intermittent surges of compressed air from a member thereof, the improvement residing in: means in combination with said conveyor between said waxed article removal means and said unwaxed article depositing means for preventing accumulation of wax on said conveyor links, said means comprising: brush means in scraping contact with said links, said brush means having a hollow core with spaced apertures therein; reservoir means for a liquid parting agent for wax type materials; and conduit means for delivering metered quantities of said parting agent from said reservoir means to said brush means, said conduit means having a portion thereof disposed in said hollow core, said portion comprising spaced apertures corresponding to said apertures in said core, said conduit means being connected to said member of said waxed article removal means so as to produce intermittent surges of compressed air in said conduit means whereby said surges of compressed air force said parting agent through said conduit means.

2. In an apparatus for applying wax to articles, which has a continuous conveyor characterized 'by a plurality of articulated flat links arranged in a pair of spaced parallel planes, said apparatus comprising article depositing means for depositing articles to be waxed on said conveyor, wax applying means for applying wax to said articles on said conveyor and waved article removal means for removing waxed articles from said conveyor with intermittent surges of compressed air from a member thereof, the improvement residing in: means in combination with said conveyor between said waxed article removal means and said unwaxed article depositing means for preventing accumulation of Wax on said conveyor links, said means comprising: brush means in scraping contact with said links, said brush means having a hollow core with spaced apertures therein, reservoir means for a liquid parting agent for wax type materials; and conduit means for delivering metered quantities of said parting agent from said reservoir means to said brush means, Said conduit means having a portion thereof disposed in said hollow core, said portion comprising spaced apertures corresponding to said apertures in said core and positioned along the top thereof, said conduit means being connected to said member of said waved article removal means so as to produce in termittent surges of compressed air in said conduit means whereby said surges of compressed air force said parting agent through said conduit means.

3. In an apparatus for applying wax to articles, which has a continuous conveyor characterized by a plurality of articulated fiat links arranged in a pair of spaced generally horizontal parallel planes and separated by a plurality of generally vertical spacing members travelling in a common path when said conveyor is moving, said apparatus comprising article depositing means for depositing articles to be waxed on said conveyor, wax applying means for applying wax to said articles on said conveyor and waxed article removal means for removing waxed articles from said conveyor with intermittent surges of compressed air from a member thereof, the improvement residing in: means in combination with said conveyor between said waxed article removal means and said unwaxed article depositing means for preventing accumulation of wax on said conveyor links, said means comprising: brush means in scraping contact with said links, said brush means including a first brush arranged to ride over said flat links in said upper plane, second brushes interposed between said planes and extending from each side of said conveyor to said path of said spacing members, and a third, arcuate brush also interposed between said planes and having two extremities mounted on the same side of said conveyor and a central portion extending into said path of said spacing members. t

4. The device of claim 3, in which said first and second brushes only are provided with means for supplying a parting agent to the bristles thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,183,672 Ritchey et a1 May 16, 1916 1,702,784 Koplin Feb. 19, 1929 1,791,728 Linfesty Feb. '10, 1931 2,079,972 Hilaise May 11, 1937 2,083,864 Puckett June 15, 1937 2,382,619 Earp Aug. 14, 1945 2,885,068 Bishop May 5, 1959 2,885,069 Bowen May 5, 1959 UNITED STATES PATENT OFFICE 1 CERTIFICATE 0F CG ,w

Patent No. 2,974,631-

March 144 1961 l I-Iarry G... Thompson it is hereby certified that error appears in the above numbered painent requiring correction and that the said Letters Patent should read as corrected below.

Column 8 lines 7 and 25 for "waved each ocemrrencm j read waxed Signed and sealed this 5th day of September 1961.

L (SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents USCOMM-DC 

